diff --git a/.changesets/add-ruby-config-file-method-to-installer.md b/.changesets/add-ruby-config-file-method-to-installer.md
new file mode 100644
index 000000000..7510c491f
--- /dev/null
+++ b/.changesets/add-ruby-config-file-method-to-installer.md
@@ -0,0 +1,6 @@
+---
+bump: patch
+type: add
+---
+
+Add the `config/appsignal.rb` Ruby config file method to installer, `appsignal install`.
diff --git a/lib/appsignal/cli/install.rb b/lib/appsignal/cli/install.rb
index 83eed246a..9709e6f12 100644
--- a/lib/appsignal/cli/install.rb
+++ b/lib/appsignal/cli/install.rb
@@ -229,35 +229,49 @@ def install_for_unknown_framework(config)
           done_notice
         end
 
-        def configure(config, environments, name_overwritten)
+        def configure(config, environments, name_overwritten) # rubocop:disable Metrics/AbcSize
           install_for_capistrano
 
           ENV["APPSIGNAL_APP_ENV"] = "development"
 
           puts "How do you want to configure AppSignal?"
-          puts "  (1) a config file"
-          puts "  (2) environment variables"
+          puts "  (1) a Ruby config file"
+          puts "  (2) a YAML config file (legacy)"
+          puts "  (3) environment variables"
           puts
           puts "  See our docs for information on the different configuration methods: "
           puts "  https://docs.appsignal.com/ruby/configuration.html"
           puts
-          loop do
-            print "  Choose (1/2): "
+          loop do # rubocop:disable Metrics/BlockLength
+            print "  Choose (1-3): "
             case ask_for_input
             when "1"
               puts
-              print "Writing config file"
+              print "Writing Ruby config file"
               periods
               puts
-              puts colorize "  Config file written to config/appsignal.yml", :green
-              write_config_file(
+              write_ruby_config_file(
                 :push_api_key => config[:push_api_key],
                 :app_name => config[:name],
                 :environments => environments
               )
+              puts colorize "  Config file written to config/appsignal.rb", :green
               puts
               break
             when "2"
+              puts
+              print "Writing YAML config file"
+              periods
+              puts
+              write_yaml_config_file(
+                :push_api_key => config[:push_api_key],
+                :app_name => config[:name],
+                :environments => environments
+              )
+              puts colorize "  Config file written to config/appsignal.yml", :green
+              puts
+              break
+            when "3"
               ENV["APPSIGNAL_ACTIVE"] = "true"
               ENV["APPSIGNAL_PUSH_API_KEY"] = config[:push_api_key]
               ENV["APPSIGNAL_APP_NAME"] = config[:name]
@@ -325,17 +339,37 @@ def rails_environments
           ).map { |o| File.basename(o, ".rb") }.sort - EXCLUDED_ENVIRONMENTS
         end
 
-        def write_config_file(data)
-          filename = File.join(
+        def write_ruby_config_file(data)
+          template = File.join(
+            File.dirname(__FILE__),
+            "../../../resources/appsignal.rb.erb"
+          )
+          write_config_file(
+            template,
+            File.join(Dir.pwd, "config/appsignal.rb"),
+            data
+          )
+        end
+
+        def write_yaml_config_file(data)
+          template = File.join(
             File.dirname(__FILE__),
             "../../../resources/appsignal.yml.erb"
           )
-          file_contents = File.read(filename)
+          write_config_file(
+            template,
+            File.join(Dir.pwd, "config/appsignal.yml"),
+            data
+          )
+        end
+
+        def write_config_file(template_path, path, data)
+          file_contents = File.read(template_path)
           template = ERB.new(file_contents, :trim_mode => "-")
           config = template.result(OpenStruct.new(data).instance_eval { binding })
 
           FileUtils.mkdir_p(File.join(Dir.pwd, "config"))
-          File.write(File.join(Dir.pwd, "config/appsignal.yml"), config)
+          File.write(path, config)
         end
 
         def new_config
diff --git a/resources/appsignal.rb.erb b/resources/appsignal.rb.erb
new file mode 100644
index 000000000..14d8e90af
--- /dev/null
+++ b/resources/appsignal.rb.erb
@@ -0,0 +1,22 @@
+# AppSignal Ruby gem configuration
+# Visit our documentation for a list of all available configuration options.
+# https://docs.appsignal.com/ruby/configuration/options.html
+Appsignal.configure do |config|
+  config.activate_if_environment(<%= environments.map(&:inspect).join(", ") %>)
+  config.name = <%= app_name.inspect %>
+  # The application's Push API key
+  # We recommend removing this line and setting this option with the
+  # APPSIGNAL_PUSH_API_KEY environment variable instead.
+  # https://docs.appsignal.com/ruby/configuration/options.html#option-push_api_key
+  config.push_api_key = "<%= push_api_key %>"
+
+  # Configure actions that should not be monitored by AppSignal.
+  # For more information see our docs:
+  # https://docs.appsignal.com/ruby/configuration/ignore-actions.html
+  # config.ignore_actions << "ApplicationController#isup"
+
+  # Configure errors that should not be recorded by AppSignal.
+  # For more information see our docs:
+  # https://docs.appsignal.com/ruby/configuration/ignore-errors.html
+  # config.ignore_errors << "MyCustomError"
+end
diff --git a/spec/lib/appsignal/cli/install_spec.rb b/spec/lib/appsignal/cli/install_spec.rb
index ff64b3200..19e735bd9 100644
--- a/spec/lib/appsignal/cli/install_spec.rb
+++ b/spec/lib/appsignal/cli/install_spec.rb
@@ -7,8 +7,10 @@
   let(:output) { out_stream.read }
   let(:push_api_key) { "my_key" }
   let(:config) { Appsignal::Config.new(tmp_dir, "") }
-  let(:config_file_path) { File.join(tmp_dir, "config", "appsignal.yml") }
-  let(:config_file) { File.read(config_file_path) }
+  let(:yaml_config_file_path) { File.join(tmp_dir, "config", "appsignal.yml") }
+  let(:yaml_config_file) { File.read(yaml_config_file_path) }
+  let(:ruby_config_file_path) { File.join(tmp_dir, "config", "appsignal.rb") }
+  let(:ruby_config_file) { File.read(ruby_config_file_path) }
   let(:options) { {} }
   before do
     stub_api_validation_request
@@ -45,22 +47,44 @@
     end
   end
 
-  define :configure_app_name do |name|
+  define :configure_ruby_app_name do |name|
+    match do |file_contents|
+      file_contents =~ /config\.name = "#{name}"/
+    end
+  end
+  define :configure_ruby_push_api_key do |key|
+    match do |file_contents|
+      file_contents =~ /config\.push_api_key = "#{key}"/
+    end
+  end
+  define :configure_ruby_environment do |env|
+    match do |file_contents|
+      match = /config\.activate_if_environment\((.*)\)$/.match(file_contents)
+      match[1].include?(env)
+    end
+  end
+  define :include_ruby_file_config do
+    match do |log|
+      log.include?("Config file written to config/appsignal.rb")
+    end
+  end
+
+  define :configure_yaml_app_name do |name|
     match do |file_contents|
       file_contents =~ /^  name: "#{name}"/
     end
   end
-  define :configure_push_api_key do |key|
+  define :configure_yaml_push_api_key do |key|
     match do |file_contents|
       file_contents =~ /^  push_api_key: "#{key}"/
     end
   end
-  define :configure_environment do |env|
+  define :configure_yaml_environment do |env|
     match do |file_contents|
       file_contents =~ /^#{env}:$/
     end
   end
-  define :include_file_config do
+  define :include_yaml_file_config do
     match do |log|
       log.include?("Config file written to config/appsignal.yml")
     end
@@ -80,14 +104,18 @@ def stub_api_validation_request
 
   alias_method :enter_app_name, :add_cli_input
 
-  def choose_config_file
+  def choose_ruby_config_file
     add_cli_input "1"
   end
 
-  def choose_environment_config
+  def choose_yaml_config_file
     add_cli_input "2"
   end
 
+  def choose_environment_config
+    add_cli_input "3"
+  end
+
   def run
     Dir.chdir tmp_dir do
       prepare_cli_input
@@ -266,18 +294,18 @@ def run
           File.delete(File.join(environments_dir, "development.rb"))
           File.delete(File.join(environments_dir, "staging.rb"))
           add_cli_input "n"
-          choose_config_file
+          choose_ruby_config_file
         end
 
         it "only configures the available environments" do
           run
 
-          expect(output).to include_file_config
-          expect(config_file).to configure_app_name(app_name)
-          expect(config_file).to configure_push_api_key(push_api_key)
-          expect(config_file).to_not configure_environment("development")
-          expect(config_file).to_not configure_environment("staging")
-          expect(config_file).to configure_environment("production")
+          expect(output).to include_ruby_file_config
+          expect(ruby_config_file).to configure_ruby_app_name(app_name)
+          expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+          expect(ruby_config_file).to_not configure_ruby_environment("development")
+          expect(ruby_config_file).to_not configure_ruby_environment("staging")
+          expect(ruby_config_file).to configure_ruby_environment("production")
 
           expect(output).to include(*installation_instructions)
           expect(output).to include_complete_install
@@ -312,8 +340,34 @@ def run
           end
         end
 
-        context "with configuration using a configuration file" do
-          before { choose_config_file }
+        context "with configuration using a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        context "with configuration using a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -322,12 +376,12 @@ def run
           it "writes configuration to file" do
             run
 
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -379,10 +433,39 @@ def run
           end
         end
 
-        context "with configuration using a configuration file" do
+        context "with configuration using a Ruby configuration file" do
+          before do
+            enter_app_name app_name
+            choose_ruby_config_file
+          end
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        context "with configuration using a YAML configuration file" do
           before do
             enter_app_name app_name
-            choose_config_file
+            choose_yaml_config_file
           end
 
           it_behaves_like "windows installation"
@@ -392,12 +475,12 @@ def run
           it "writes configuration to file" do
             run
 
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -439,20 +522,20 @@ def run
 
         it "prompts the user to fill in an app name" do
           enter_app_name app_name
-          choose_config_file
+          choose_ruby_config_file
           run
 
           expect(output).to include("Installing for Ruby on Rails")
           expect(output).to include("Unable to automatically detect your Rails app's name.")
           expect(output).to include("Choose your app's display name for AppSignal.com:")
-          expect(output).to include_file_config
+          expect(output).to include_ruby_file_config
           expect(output).to include_complete_install
 
-          expect(config_file).to configure_app_name(app_name)
-          expect(config_file).to configure_push_api_key(push_api_key)
-          expect(config_file).to configure_environment("development")
-          expect(config_file).to configure_environment("staging")
-          expect(config_file).to configure_environment("production")
+          expect(ruby_config_file).to configure_ruby_app_name(app_name)
+          expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+          expect(ruby_config_file).to configure_ruby_environment("development")
+          expect(ruby_config_file).to configure_ruby_environment("staging")
+          expect(ruby_config_file).to configure_ruby_environment("production")
         end
       end
     end
@@ -499,8 +582,34 @@ def run
           end
         end
 
-        describe "configure with a configuration file" do
-          before { choose_config_file }
+        describe "configure with a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        describe "configure with a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -509,12 +618,12 @@ def run
           it "writes configuration to file" do
             run
 
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -569,8 +678,34 @@ def run
           end
         end
 
-        describe "configure with a configuration file" do
-          before { choose_config_file }
+        describe "configure with a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        describe "configure with a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -579,12 +714,12 @@ def run
           it "writes configuration to file" do
             run
 
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -636,8 +771,34 @@ def run
           end
         end
 
-        describe "configure with a configuration file" do
-          before { choose_config_file }
+        describe "configure with a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        describe "configure with a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -646,12 +807,12 @@ def run
           it "writes configuration to file" do
             run
 
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -706,8 +867,33 @@ def run
           end
         end
 
-        describe "configure with a configuration file" do
-          before { choose_config_file }
+        describe "configure with a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        describe "configure with a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -715,12 +901,12 @@ def run
 
           it "writes configuration to file" do
             run
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do
@@ -776,8 +962,33 @@ def run
           end
         end
 
-        describe "configure with a configuration file" do
-          before { choose_config_file }
+        describe "configure with a Ruby configuration file" do
+          before { choose_ruby_config_file }
+
+          it_behaves_like "windows installation"
+          it_behaves_like "capistrano install"
+          it_behaves_like "demo data"
+
+          it "writes configuration to file" do
+            run
+            expect(output).to include_ruby_file_config
+            expect(ruby_config_file).to configure_ruby_app_name(app_name)
+            expect(ruby_config_file).to configure_ruby_push_api_key(push_api_key)
+            expect(ruby_config_file).to configure_ruby_environment("development")
+            expect(ruby_config_file).to configure_ruby_environment("staging")
+            expect(ruby_config_file).to configure_ruby_environment("production")
+          end
+
+          it "completes the installation" do
+            run
+
+            expect(output).to include(*installation_instructions)
+            expect(output).to include_complete_install
+          end
+        end
+
+        describe "configure with a YAML configuration file" do
+          before { choose_yaml_config_file }
 
           it_behaves_like "windows installation"
           it_behaves_like "capistrano install"
@@ -785,12 +996,12 @@ def run
 
           it "writes configuration to file" do
             run
-            expect(output).to include_file_config
-            expect(config_file).to configure_app_name(app_name)
-            expect(config_file).to configure_push_api_key(push_api_key)
-            expect(config_file).to configure_environment("development")
-            expect(config_file).to configure_environment("staging")
-            expect(config_file).to configure_environment("production")
+            expect(output).to include_yaml_file_config
+            expect(yaml_config_file).to configure_yaml_app_name(app_name)
+            expect(yaml_config_file).to configure_yaml_push_api_key(push_api_key)
+            expect(yaml_config_file).to configure_yaml_environment("development")
+            expect(yaml_config_file).to configure_yaml_environment("staging")
+            expect(yaml_config_file).to configure_yaml_environment("production")
           end
 
           it "completes the installation" do